Unit heater



Dec. 15, 1936. J E sMlTH 2,064,389

UNIT HEATER Filed Nov. 5, 1932 2 Sheets-Sheet 1 CURRENT SUPPLY Dec. 15 1936. J sMlTH 2,064,389

UNIT HEATER Filed Nov. 5, 1932 2 Shee+1-Sheet 2 x 5 16%, 7AM 9 W Patented Dec. 15, 1936 UNITED STATES PATENT OFFICE mn'r ans-ma John E. Smith, Belleville, IlL, assignor to Knapp Monarch Company, Bellevillc, 111., a corporatlon of The object of my invention is to provide s.

unit heater which is simple, durable and comparatively inexpensive to manufacture.

A further object is to provide a unit heater 5 comprising an upright casing with electrically energized heating means therein for heating air, the casing being open at its bottom so that air can. circulate thereinto whereupon it will be heated and will circulate upwardly, the side of 10 the casing having discharged openings for it to circulate out through into the room in which the unit heater is positioned.

Still a further object is to provide an electric heater of radiator-like appearance, it being 15 formed of a casing having discharge openings in one side and adjacent the top thereof, means being provided for introducing air into the casing and heating it before it is discharged thr u h d, openin s.

Still a further object is to provide a heating element in the unit heater which comprises a pair of rod-like, electric heating units, spaced vertical fins being provided along the heating units for more readily radiating heat from the 25 heating units to the air being circulated through the device.

Still a further object is to provide a thermostatic switch i'or automatically controlling the energization and de-energization of the electric 3o heating element, a signal light being provided to indicate whether or not the heating element is energized and being discernible through a lens in the side of the casing.

Still a further object is to provide frictional mounting means for the ends ofv the electric heating elements so 'they can expand relative to the casing of the device.

With these and other objects in view -my invention consists in the construction, arrange- 40 ment and combination of the various parts of my device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which:

45 Figure 1 is a perspective view of a unit heater v embodying my invention.

Figure 2 is an enlarged vertical sectional view on the line 2-2 of Figure 1.

Figure 3 is a horizontal sectional view on the 50 IineS -JofFIgureIshQWingthepartsonan enlarged scal'e.

Figure 4 is a sectional view Oil-the line ofFigure3.

Figm'e5isasectionalviewontheline55 56ofFlgme4showingaticswitchfor automatically controlling the heating elements. Figure 6 is an enlarged sectional view on the Figure 7 is a sectional view on the line -I--| of Figure 4; and 5 Figure 8 is an electric diagram of the wiring of the unit heater. 7

On the accomp ny drawing I have used the reference character A to indicate generally a casing. The casing A is open at its lower end 10 as shown in Figin'e 2 and is spaced above a floor surface II by supporting legs l2.

' The upper end of the casing is open but a removable cover I4 is provided therefor. In one side of the casing, discharge openings l5 are p ovided.

Within the casing A, I provide a pair of heating elements B. Each one comprises a tubular metal casing l 6 having a resistance coil 18 therein insulated by argillous material 20, for instance, 20 which is originally inserted into the casing It in a plastic state.

A terminal 22 is provided for each end of each 'heating element B. The terminals 22 are insulated from the casing l6 by sleeves 24 of insula- 25 tion. The endof each resistance wire l8 extends through a longitudinal slot 26 of its particular terminal screw 22in order to pass through the bushing 24. This is more fully disclosed in my copending application "Serial No. 641,016, filed 3 November'3, 1932.

' The heating elements B are supported frictionally by clamp bars 28. The clamp bars 28 are secured by bolts 30 to supp rting Plates 32 (see Figln'e 7). A frictional mounting of this 35 character permits expansion and contraction of the heating elements B without undue strain.

Threaded-on the heating elements B are radiation fins 24. Each one has a pair of hubs 36 to encircle the heating elements. These retain the fins in their proper position at right angles to the heating elements B.

Side members 38 are provided for the fins 24. The side members "are secured to the ends of three supporting members 40 which are notched ,5 as indicated at 42 to flt over the heating elements B. The side members 38 are provided with flanges 44 slightly overlapping the edges of the fins I4.

The combination of heating elements B, fins 34, side members 38 and supports 40\provides a heating unitwhich can be readily inserted in or removed from the casing A. Only the two bolts ll are to hold this mil; in its proper position. 7

Within the casing A adjacent the lower part thereof and preferably adjacent one end of the heating elements B, I provide a thermostatic switch C. The switch C comprises a bimetal arm 48 and a spring arm 54 carrying coacting contacts 52 and 54, respectively. An adjusting screw 56 having an insulated head 58 and a lock nut 60 is shown in 5. The screw can be manipulated to adjust the spring and thereby the position of the contact 54 for requiring more or less predetermined heat to open the thermostatic switch C. 7

Within the casing A, I provide a signal light socket 62. A signal light 64 is mounted within the socket and aims 6G is mounted in the wall of the casing A through which the signal light 64 is discernible. The signal-light 64 is preferably of the neon type. 1

Referring to Figure 8, it will be noted that the heating elements B and the signal light 64 are connected in parallel with each other and all are connected in series with the thermostatic switch C. Thus when a predetermined degree of heat is reached within the casing A, the thermostatic switch opens for tie-energizing the heating elements and at the same time the light 84 is extinguished whereby to indicate the action of the thermostat.

I preferably provide a switch 68 which is manually controlled. It is mounted on one end of the casing A.

In the operation of the device, the switch 68 may be turned to the on position whereupon the heating elements B, the signal light 64 and the thermostatic switch C will be energized. Upon the interior of the casing A reaching a predetermined temperature, the bimetal arm 48 will move to the dotted line position of Figure 8 for opening the circuit until the heating unit has cooled down to a point where the contact 52 on the bimetal arm will again engage the contact 54 for re-establishing the heating circuit.

Some changes may be made in the construction and arrangement of th of my device without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents, which may be reasonably included within their scope.

I claim as my invention:

1. In a unit heater, an upright casing, inlet and outlet openings at the top and bottom thereof, a heating element in said casing comprising a tube-like heating member and a plurality'of fins threaded thereon, an electric heating element encased in said heating member and means for confining said fins within said casing comprising a channel shaped member along each side of the casing, the ends of the fins fitting between the flanges thereof.

2. In a unit heater, a casing, a heating element in said casing comprising a tube-like member and a plurality of fins threaded thereon, an electric heating element encased in said heating memher and means for confining said fins within said casing against vertical movement relative thereto comprising a pair of channel-shaped members supported by said casing, the ends of said fins loosely fitting between the flanges thereof and thereby movable individually, horizontally relative thereto.

JOHN E. SMITH. 

